Engine cooling system radiator and fan shroud

ABSTRACT

An engine cooling system including a fan rotatably mounted on an engine, a fan shroud secured to a radiator, and a foam ring secured to an inner portion of the shroud immediately radially adjacent the tips of the fan blades such that the blades cut a clearance in the foam ring during operation as required to compensate for any relative movement between the engine and radiator to thus provide for a highly efficient fan-shroud clearance.

United States Patent 1191 Small Mar. 26, 1974 [54] ENGINE COOLING SYSTEM RADIATOR 3,487,519 1/1970 Davidson 415/174 UX AND FAN S R 3,519,282 7/1970 Davis 415/214 UX 3,547,455 12/1970 Daunt 415/214 UX [75] In n Robert 0 Small, g, Mleh- 3,575,427 4/1971 Lapac etal. 415/174 ux 3,689,971 9/1972 Davidson 415/174 X [73 1 Asslgnee' Minors Cmpm'atmn 3,756,741 9/1973 Woell, Jr. 415/174 Detroit, M1ch.

[ Filedi 1973 Primary Examiner-A1 Lawrence Smith [21] Appl No: 339197 Attorney, Agent, or Firm-John P. Moran 52 US. Cl 123/4149, 415/174, 415/214 1 ABSTRACT [51] '1 CL F01! 11/10 F04d 29/021 F04d 29/08 An engine cooling system including a fan rotatably [58] Field of Search 123/4102, 41.04, 41.05, mounted on an engine, a fan Shroud secured to a radi l23/4l-49; 415/1741 119 ator, and a foam ring secured to an inner portion of the shroud immediately radially adjacent the tips of [56] References cued the fan blades such that the blades cut a clearance in UNITED TATE PA E T the foam ring during operation as required to compen- 3,053,694 9/1962 Daunt et a1. 415/174 x Sate for ny r l ov men be ween the engine 3,294,315 12/1966 Stewart et a1 415/214 and radiator to thus provide for a highly efficient fan- 3,313,476 4/1967 Ross 415/174 UX shroud clearance. 3,321,931 5/1967 Lehmkuhl 415/119 3,346,175 10/1967 Wiles 415/214 UX 4 Claims, 2 Drawing Figures ENGINE COOLING SYSTEM RADIATOR AND FAN SHROUD -This invention relates generally to engine cooling systems and, more particularly, to an improved fan-shroud arrangement therefor.

In current motor vehicles the cooling fan normally revolves in a shroud, the relationship therebetween providing a higher efficiency than for a shroudless fan, in drawing air through the radiator to cool the liquid which is circulated through the radiator and engine to control the temperature of the latter. It is well known that the less differential there is between the external diameter of the fan and the internal diameter of the shroud the more efficient will be the cooling process.

However, it is also well known that, with the shroud mounted on the radiator and the fan rotatably mounted on the engine, relative radial movement of the fan and the shroud is apt to occur at various times, such as when the engine is started and/or when the vehicle is traveling over rough terrain. Because of this, it has been the custom to provide a substantial annular clearance between the external diameter of the fan blades and the internal diameter of the shroud.

In lieu of the predetermined annular clearance provision, it has been proposed to provide a fan shroud having an internal venturi-shaped section and an external box section, wherein the two sections are interconnected by a suitable flexible sealing ring, permitting the two sections to be mounted respectively on the engine and the radiator, thus avoiding any relative movement between the fan and the adjacent venturi-shaped shroud section (U.S. Pat. No. 3,144,859 Walton, dated Aug. 18,1964).

A general object of this invention is to provide an improved simplified fan shroud arrangement which takes into consideration the above-described problem and efficiently compensates for same.

Another object of the invention is to provide conventionally-mounted fan and shroud components which automatically compensate for the above described problem. I

A further object of the invention is to provide an improved fan and shroud arrangement wherein the shroud includes a foam insert positioned immediately radially adjacent the outer tips of the cooling fan blades such that any relative movement of the conventional engine-mounted fan with respect thereto will merely result in the fan blades cutting a clearance in the foam insert, resulting in a highly efficient cooling operation commensurate with the formation of the closest practicable operational clearance therebetween.

These and other objects and advantages of the invention will be apparent when reference is made to the following description and accompanying drawings, wherein:

FIG. 1 is a fragmentary side view of an engine cooling arrangement embodying the invention; and

FIG. 2 is an exploded view of the fan and shroud arrangement embodied in the invention.

Referring now to the drawings in greater detail, FIG. 1 illustrates a vehicular radiator and an engine 12 axially aligned therewith and spaced a predetermined distance apart therefrom. A cooling fan 14 including blades 16 is rotatably mounted on a shaft 18 on the front of the engine 12 and driven by a conventional belt 20 and pulley 22 combination.

A fan shroud assembly 24 includes a rectangularshaped section 26 (FIG. 2) with mounting tabs or brackets 28 for mounting on the engine side of the radiator 10, the tabs 28 serving to permit the shroud assembly 24 to be aligned at installation with the cooling fan blades 16. A circular section 30 is formed on the rectangular section 26 and rigidly supported thereon by braces 32.

A substantially venturi-shaped foam ring 34 is secured to the inner surface 36 (FIG. 1) and rearwardly extending edge 38 of the circular shroud section 30 in any suitable manner, such as by being glued thereon. The smallest inside diameter of the foam ring 34 is substantially the same diameter as the outermost diameter of the blades 16, the shroud assembly 24 being mounted on'the radiator 10 at assembly such that the ring 34 practically touches or just clears the outer edges of the blades 16 (FIG. 1).

Now, any relative movement of the engine 12 with respect to the shroud assembly 24, as a result of vibrations, for example, will cause the respective fan blades 16 outer edges to cut a clearance in the foam ring 34. There results a highly efficient cooling operation due to the formation of the closest practicable operational clearance 40 between the ring 34 and the blades 16, short of mounting the shroud on the engine itself.

It should be apparent that the invention provides an engine cooling system incorporating conventional components with a simplified shroud additive for automatically and efficiently providing the most efficient operational clearance between the fan and the shroud.

While but one embodiment of the invention has been shown and described, other modifications thereof are possible.

I claim:

1. For use with a vehicular engine and radiator, an engine cooling system comprising a fan including a plurality of blades and rotatably mounted on said engine intermediate said engine and said radiator, a shroud assembly having a mounting portion mounted on said radiator and a shroud portion extending axially past the outer tips of said plurality of blades, and a foam ring secured to the inner surface of said extended shroud portion immediately adjacent said outer tips of said plurality of blades, said tips serving to cut a clearance in said foam ring compensating for any relative movement between said engine and said radiator.

2. For use with a vehicular engine and radiator, an engine cooling system comprising a fan including a plurality of blades and rotatably mounted on said engine intermediate said engine and said radiator, a shroud having a rectangular section mounted on said radiator and a circular section formed on said rectangular section and extending axially past the outer tips of said plurality of blades, and a foam ring secured to the inner surface of said circular shroud section immediately adjacent said outer tips of said plurality of blades, said tips serving to cut a clearance in said foam ring compensating for any relative movement between said engine and said radiator.

3. For use with a vehicular engine and radiator, an engine cooling system comprising a fan including a plurality of blades and rotatably mounted on said engine intermediate said engine and said radiator, a shroud having a rectangular section mounted on said radiator and a circular section formed on said rectangular section and extending axially past the outer tips of said plurality of blades, and a foam ring having a venturishaped radial inner surface and a substantially cylindrical radial outer surface, said outer surface being secured to the inner surface of said circular shroud section immediately adjacent said outer tips of said plurality of blades, said tips serving to cut a clearance in said venturi-shaped inner surface of said foam ring compensating for any relative movement between said engine and said radiator.

4. For use with a vehicular engine and radiator, an engine cooling system comprising a fan including a plurality of blades and rotatably mounted on said engine intermediate said engine and said radiator, a shroud having a rectangular section mounted on said radiator and a circular section formed on said rectangular section and extending axially past the outer tips of said plurality of blades, and a foam ring having a venturishaped radial inner surface and a two-diameter radial outer surface, the smaller radial outer surface being secured to the inner surface of said circular shroud section adjacent the end thereof and immediately adjacent said outer tips of said plurality of blades, the shoulder between the two outer surfaces abutting against said end of said circular shroud section, said tips serving to cut a clearance in said venturi-shaped inner surface of said foam ring compensating for any relative movement between said engine and said radiator. 

1. For use with a vehicular engine and radiator, an engine cooling system comprising a fan including a plurality of blades and rotatably mounted on said engine intermediate said engine and said radiator, a shroud assembly having a mounting portion mounted on said radiator and a shroud portion extending axially past the outer tips of said plurality of blades, and a foam ring secured to the inner surface of said extended shroud portion immediately adjacent said outer tips of said plurality of blades, said tips serving to cut a clearance in said foam ring compensating for any relative movement between said engine and said radiator.
 2. For use with a vehicular engine and radiator, an engine cooling system comprising a fan including a plurality of blades and rotatably mounted on said engine intermediate said engine and said radiator, a shroud having a rectangular section mounted on said radiator and a circular section formed on said rectangular section and extending axially past the outer tips of said plurality of blades, and a foam ring secured to the inner surface of said circular shroud section immediately adjacent said outer tips of said plurality of blades, said tips serving to cut a clearance in said foam ring compensating for any relative movement between said engine and said radiator.
 3. For use with a vehicular engine and radiator, an engine cooling system comprising a fan including a plurality of blades and rotatably mounted on said engine intermediate said engine and said radiator, a shroud having a rectangular section mounted on said radiator and a circular section formed on said rectangular section and extending axially past the outer tips of said plurality of blades, and a foam ring having a venturi-shaped radial inner surface and a substantially cylindrical rAdial outer surface, said outer surface being secured to the inner surface of said circular shroud section immediately adjacent said outer tips of said plurality of blades, said tips serving to cut a clearance in said venturi-shaped inner surface of said foam ring compensating for any relative movement between said engine and said radiator.
 4. For use with a vehicular engine and radiator, an engine cooling system comprising a fan including a plurality of blades and rotatably mounted on said engine intermediate said engine and said radiator, a shroud having a rectangular section mounted on said radiator and a circular section formed on said rectangular section and extending axially past the outer tips of said plurality of blades, and a foam ring having a venturi-shaped radial inner surface and a two-diameter radial outer surface, the smaller radial outer surface being secured to the inner surface of said circular shroud section adjacent the end thereof and immediately adjacent said outer tips of said plurality of blades, the shoulder between the two outer surfaces abutting against said end of said circular shroud section, said tips serving to cut a clearance in said venturi-shaped inner surface of said foam ring compensating for any relative movement between said engine and said radiator. 